Natural Heritage

Marsh - The Between Land

Indians called marshes "the between land" because they were neither land nor water. Native North Americans looked on marshes as storehouses of food - wild rice, fish, and ducks - but many settlers saw little value in them.They set about to conquer marshes and many were diked and drained, and the rich black soil was used for growing vegetables.

As a result of these attitudes, very little of southern Ontario's once extensive marshland has survived. The marsh in Point Pelee, although only a remnant of a much larger marsh, is still one of the largest remaining segments in southern Ontario. The marsh's size and the tremendous diversity of life that it supports have contributed to it being named a RAMSAR site, indicating that it is a wetland of international significance.

At first glance, there is a sameness about Point Pelee's marsh. A sea of cattails stretches as far as the eye can see. Set into this sea is a mosaic of various-sized ponds. Water is a key element in any marsh. Beneath its surface live such animals as zooplankton (microscopic animals) and fish. The surface is a good place to look for frogs, turtles, muskrats, snakes, and various insects. Darting over the water are the flying adults of aquatic insect larvae, including dragonflies and damselflies.

Sunfish Surprise

Plants and animals moved to colonize Southwestern Ontario as soon as it was free of the last glacier. The first colonizers were the hardiest, but, as conditions improved, even organisms less well adapted to cold had their chance. It is a process which continues as more species expand their range northward even today.

One such creature is a fish with the peculiar name, Warmouth. Warmouths are members of the sunfish family that have very large mouths and aggressive behaviour, which might explain their name. Until recently, the Warmouth's range skirted the Great Lakes. Studies have shown that this range has been expanding for at least the last 20 years, and it was inevitable that they would eventually reach Canadian waters.

Verification of this came on June 5, 1966 when Roger Roy, a seasonal naturalist with the Ontario Ministry of Natural Resources, captured one at Rondeau Provincial Park. Five additional specimens were caught there over the next four years, but none have been seen there since.

However, on March 31, 1983, Park Warden Gary Mouland netted a Warmouth in the marsh at Point Pelee while conducting a year-long inventory study to update the park's fish species list. From June until October of that year, Warden Mouland captured another 46 Warmouths, of which 28 were adults, and the remaining 18 were subadults. This means that Warmouths at Point Pelee have managed to establish a breeding population.

Forest

One of Point Pelee's most intriguing features is its forests. This is mainly due to their uniqueness and large variety.

For example, in some of the more open areas the forests are just beginning to develop. Here, the trees are relatively widely spaced. High temperatures, poor soils and exposure to the wind limit growth to only those tree species that can cope with these conditions. Included in this group are red cedars, cottonwoods, willows, hop trees, and honey locusts.

Finding honey locusts growing in this situation is extremely unusual. Native honey locusts have a very limited range in Canada. They usually grow in well-protected, damp areas. This almost field-like setting in which they exist at Point Pelee is the only known example in Canada.

In contrast to these newly developing areas, the most mature parts of the forest are like a jungle. In the summer, light can hardly penetrate the dense foliage. Vines add to the jungle likeness. In search of sunlight, wild grape, Virginia creeper, and poison ivy vines hang rope-like from the tops of some of the tallest trees. Much of this forest has a distinctly southern flavour. The most common tree here is the hackberry. Finding a forest of them in Canada is really surprising, but the hackberry is not the only southern tree to be found in Point Pelee's forest. Others include black walnut, chinquapin oak, swamp white oak, tuliptree, red mulberry, blue ash, and sassafras.

Another feature of this type of forest is the rich assortment of flowering plants. In the spring, the forest floor is covered with may-apple, sweet cicely, columbine and dutchman's breeches, all hurrying to flower before they are shaded out.

Some survive the shade well. Tiny herb-robert blooms from May to November. It is joined in early summer by appendaged waterleaf and false solomon's-seal, and then, in the deep shade of summer, by tall bellflower and lopseed. In the fall, a fringe of woodland sunflower, goldenrod, and a bevy of asters provide one final splash of colour before the onset of winter.

In the more northerly areas of the Park, Point Pelee's southern flavour is tempered with an influx of species more typical of central Ontario's mixed-wood forest. Included is a sprinkling of sugar maple, basswood, a variety of species of oak, and a few stands of mature white pine.

The Swamp Forest

People often incorrectly call marshes "swamps." Marshes are wet areas in which the most common plant species are annuals, such as cattails and bulrushes. Swamps are similar to marshes in that they are wetlands, but here the dominant plants are trees.

Point Pelee has both a marsh and a swamp. The swamp is situated directly south of the marsh in an area which was once a series of beach ridges. It developed when water collected in the troughs between the ridges. The amount of water is controlled by the lake. When levels are high, more water percolates through the sand, flooding the troughs. As lake levels fall, so do water levels in the troughs. Thus, growing conditions here can vary considerably, depending on long-term fluctuations in lake levels.

At present, the swamp forest is quite open. Thirty years ago, its character was very different. Then, the swamp forest had many trees, predominantly white elm. Trees that live in wet sites develop shallow, widespread root systems which intertwine to support each other. Dutch elm disease killed all the elms, and severely weakened this support system. Record high water levels during the early 1970s caused extensive flooding, resulting in further instability. Strong northeasterly storms during this same period didn't help. Weakened by the disintegration of their support system, many trees have toppled.

At first glance, it appears that Dutch elm disease, strong winds, and high water levels have all but destroyed the conditions needed for the survival of Point Pelee's swamp inhabitants. This is true in some instances; but in other cases, these are the very conditions that many kinds of plants and animals seek. Dead trees are the preferred nesting sites of tree swallows, wrens, wood ducks, woodpeckers, great horned owls, and on occasion, even the rare prothonotary warbler.

In fact, this southern warbler seldom nests in any place other than the cavity of a rotting stump surrounded by the water of a swamp forest. In Canada, this limits their range to a few sites along Lake Erie's north shore which contain this type of habitat. One surprising adaption displayed by this warbler, which helps its young survive in the swamp, is that nestlings are expert swimmers. Should they accidentally fall into the water, they happily paddle to the nearest high ground.

While dead trees are important to these warblers and other birds, not all the trees are dying. Silver maple and sycamore are two species that have survived the swamp's changes. Silver maples display the typical maple leaf, while the sycamore is easily identified by its bark, which appears to be peeling. With a few exceptions, sycamores are found only in the Carolinian Zone.

All forests have understories made up of shrubs and flowering plants. One of the most attractive swamp shrubs is the spicebush, especially in autumn when it is covered in bright red berries. Spicebush is another of Point Pelee's Carolinian species, but one which brings with it a bonus ... the spicebush swallowtail butterfly. The caterpillar of this beautiful, blue-black swallowtail feeds primarily on spicebush and so, at least in this part of Canada, it is a common sight on summer days.

The attractions of the swamp are not only visual. The swamp forest can be a noisy place in spring, when the aptly named spring peepers are in full voice. Spring peepers are thumbnail-sized frogs found primarily in the swamp forest. Their high-pitched peeping seems to come from everywhere, but they are almost impossible to find. They are joined in this spring chorus by other frogs and toads, the humming of insects, and the calls of migratory birds.

By summer, the sloughs of the swamp forest are covered with duckweed. This all but shields out other growth. However, blue flag, loosestrife, bonefest, and joe-pye weed are a few plants that are able to protrude above the duckweed, providing a splash of colour in this otherwise green carpet.

As fall approaches, jewelweed borders the wet areas. When its orange blossoms hang with dew, it truly takes on a jewel-like appearance. Its other common name may not be as easy to understand unless you're familiar with how it spreads its seeds. When ripe, the seed pods are spring-loaded. If they are touched, they explode, expelling seeds in all directions. To the unaware these explosions can be startling. That's why it is sometimes also called "Touch-Me-Not."

Campers in the Trees

A common sight at Point Pelee in late summer and autumn is the large, white tent-like tangles in the trees. Speculation as to what they are ranges from the handiwork of giant spiders to the workings of tent caterpillars. Those that guess tent caterpillars are closest to the correct answer. These webs are made by a caterpillar known as the fall web worm, and it is a close relative of the tent caterpillars.

But they are not the same. Fall web worms are not nearly as destructive as tent caterpillars. As the name implies, infestations usually occur in the autumn. This means that the affected trees have had the use of their leaves for most of the growing season, and have gathered sufficient stores of food to easily produce new foliage next spring. In fact, some trees that have been stripped in early infestations have been known to put out a second set of leaves. This means that there are insufficient reserves to go through the process again in the spring, and thus some trees die.

As well, unlike tent caterpillars, fall web worms do not leave their web to feed. As protection against birds, they simply expand their web around their food source. This makes the web look very large in comparison. Fall web worms also prefer the open edges of forests, so what we see along the road is a concentration, and is not representative of the rest of the forest.

The web acts as a very effective defence. Most birds are unable to feed on fall web worms because the webs clog their intestinal tracts. Only the yellow-billed and black-billed cuckoo get around this problem. Periodically, they regurgitate their stomach lining, thus cleaning out the webbing and leaving them free to start again.

Tunnel Vision

If visitors to Point Pelee were asked to list the Park's most notable animals, it's almost a sure bet that there would be little, if any, mention of eastern moles. Yet in the eyes of some scientists and Park officials, eastern moles are the most important mammal found in the Park. This is because Point Pelee is home to Canada's only large population of these especially interesting creatures.

Elsewhere on the continent outside of Canada, eastern moles enjoy the widest distribution of all species of North American moles, and are often thought of as nuisances because of what they do to lawns. But in Canada just the opposite is true. Because there are so few, eastern moles have been given the highest level of protection within Point Pelee.

If you've never seen an eastern mole you're not alone. They are strictly fossorial, which means that to find them, you have to crawl around underground. This would be difficult for us, but moles have been at it for so long that they are extremely well-equipped for a life of tunnelling.

The most notable features of a mole is the development of its front quarters. An eastern mole's front legs are short and powerful, and their shoulders have rotated so that the palms of their oversized feet face outwards. There are five toes on each front foot and each comes equipped with a flat heavy nail that looks like a little trowel, designed for digging. And dig they do! Throughout their lives, eastern moles construct a maze of shallow runways and deeper nesting chambers. Studies have shown that these tunnels can be as long as 1 000 metres (3 000 feet), and have been known to be dug at the rate of over a metre (three feet) an hour.

The nose of an eastern mole is one of the most striking features of its face. It is relatively long, pointed and nearly hairless. It is also extremely flexible and sensitive, and serves as the animal's main sensory organ through which it learns about its environment. Eastern moles use this highly developed sense of smell along with a refined sense of touch to locate food. They eat a variety of small animals, but they are attracted most to white grubs and earthworms. Features that aren't needed in the mole's dark world have degenerated. For example, moles probably have only enough eyesight to distinguish light from dark. Their eyes are so small that they can hardly be seen through their fur.

Occasionally, a mole will poke its pink snout through the loose soil, but you're not likely to see any more of him than that. However, you'll know he's been around. The raised roofs of their tunnels or the "pushups" that mark the excavations of their deeper nesting chambers are an indication of a mole's presence. Eastern moles prefer soft, moist humic soil like that found in the Park's forests. So watch for the telltale signs of Point Pelee's most important mammal.

Fields

With the arrival of European settlers, large areas of Point Pelee were cleared for farming. Later, as farming declined, these man-made fields were abandoned, creating new open areas where native plants capable of surviving hot, dry conditions could thrive.

This reforestation of abandoned crop fields occurs in a series of stages. The transition from one stage to another is called succession. During each successive stage, different associated plant species will dominate. At first, grasses, milkweeds, puccoons, mullein and wild grape dominate. They are followed, in turn, by shrubs and sun-loving trees. Eventually, the whole process culminates in the field once again becoming forest.

Many of the plants that grow in Point Pelee's fields are those that one would expect in such an environment throughout most of Canada. But, as with the Park's other habitats, there are some special ones too. For example, most people are familiar with common milkweed, but there are at least three other species of this plant in the Park. Two of these, butterfly weed and green milkweed, are worth finding. The flowers of all other Canadian milkweeds pale when compared to the brilliant orange blossoms displayed by butterfly weed. And, although green milkweed may not be as colourful, its claim to fame is its rarity in Ontario.

As for shrubs, burning bush (Euonymus atropurpureus) is both beautiful and rare. It is unique to the Canadian Carolinian zone, and its red flowers and bright berries make it a worthy rival even to butterfly weed.

The plant that draws the most attention in Point Pelee's fields is the prickly pear cactus. It is so rare in Canada that the Ontario government in the summer of 1987 added it to its official list of protected plants.

Fields are good areas to look for a variety of wildlife. Some can be quite obvious to spot, such as deer, cottontail rabbits and butterflies. Others are more difficult to find. Coyotes are large enough that they should easily be seen, except that they are usually quite secretive. There is usually one family of coyotes, sometimes two, in the entire Park. Shrews and mice are common, but because they are so small they can hide easily in the tall grass.

Many birds nest in fields and, like plants, each successional stage is characterized by its own nesters. For example, meadowlarks and ring-necked pheasants prefer grassy areas or locations with some shrubby growth. As the shrubs thicken, field sparrows, common yellowthroats, northern cardinals and rufous-sided towhees become more common. This is also the preferred habitat of two of Point Pelee's southern nesters, the yellow-breasted chat, and the white-eyed vireo. As red cedars invade, blue-gray gnatcatchers, wood pee-wees, yellow-throated vireos, and great-crested flycatchers join in. Finally, Point Pelee's wooded areas see nesting red-eyed vireos and yellow-billed cuckoos, along with the occasional wood thrush.

Fields are also a good place to look for some of Pelee's reptiles. Perhaps you might catch a glimpse of eastern Canada's only lizard, the five-lined skink or Point Pelee's largest snake, the fox snake. What you are more likely to see though, are garter snakes. The Park's garter snakes come in a variety of colours and patterns. Most people are familiar with the striped version, but at Point Pelee there are also melanistic garters: that is, ones that are mostly jet black. All snakes found in the Park are non-poisonous and harmless.

Jewels of the Insect World

Point Pelee is most associated with monarch butterflies, however, some 60 other species have been seen here over the last century. As might be expected, some of these are not found in any other part of the country.

Certain butterflies are particular about what they eat during their lives as caterpillars. The availability of these special host plants therefore limits their range. One reason why Point Pelee attracts some of these rare Canadian butterflies is the presence of specific plants which have a limited distribution in Canada. For example, the presence of hackberry, snout, and tawny emperor butterflies is due to the fact that the caterpillars of these species feed largely on hackberry trees, and Point Pelee is one of the few spots in Canada where this tree is common.

A similar relationship sustains the spectacular giant swallowtail, one of the most memorable of Point Pelee's butterflies because of its impressive size. Although giant swallowtails occur only sparingly in other parts of the country, they are a common sight here due to the caterpillar's principal host plant, the hop tree.

Not all butterflies found in the Park are native to the area. Point Pelee's southern extension places it closer than any other part of Canada to the northern range of a variety of butterflies. Because of this, rarities will sometimes accidentally wander into the Park, especially when riding strong, southerly weather fronts.

The greatest variety of butterflies is seen in July. More than one-half of all of Point Pelee's species are active then. Look for them as they drift and dance across the open fields in search of flowers. In such a setting, it is not hard to understand why these beautifully coloured creatures are sometimes referred to as "The Jewels of the Insect World."

The Living Pincushion

Most people think of cactus as a desert plant, and it surprises them to find it growing wild at Point Pelee. To them, the Park is anything but a desert. But many of Point Pelee's open fields are sandy and in the hotter months they can quickly become very dry, much like deserts, providing an ideal habitat for cactus. Interestingly, cacti are uncommon in Canada not because of a lack of suitable habitat, but rather because of their inability to survive our winters.

Of the 2 500 or so species of the world's cacti, only about 50 are "cold resistant." Four species of these cold-resistant cacti are found in Canada. Of these three belong to the Prickly Pear family. To confuse the issue, all are commonly called prickly pear cactus, or just cactus.

Three of these species are relatively widespread throughout the prairies. The scientific name for the remaining species is Opuntia humifusa, and it's the prickly pear cactus found at Point Pelee. Of all of Canada's cacti, this prickly pear has the smallest distribution. It is only native to extreme southwestern Ontario, and even there, except for Point Pelee, it is quite rare.

Opuntia humifusa makes up for its small distribution by being the largest Canadian cactus. Its flattened pads can reach a size of 10 to 15 centimetres long (4 to 6 inches) by 8 to 10 centimetres wide (3 to 4 inches) and 1 centimetre thick (0.4 inches). A few long, sharp spines project from the top of each pad while the remainder appears naked. But don't be fooled, the rest of the pad is actually covered in almost invisible, silver-like barbs. If touched, these barbs can be very painful, especially if they lodge in the skin and fester.

However, all might be forgiven when the visitor sees the plant's most striking feature: its large, waxy, rose-like yellow flower. In late June and early July, this special Point Pelee treat is an attraction that, all on its own, makes a trip to the Park a must.

A Mimic From Among the Reptile Family

Originally, at least 10 of the 16 different species of snakes known to southern Ontario were found at Point Pelee. Today, there are at best only five species left and the continuing presence of the eastern milk snake is questionable. Gone are both the massasauga and timber rattlesnakes, and the hognose snake, the blue racer and the black rat snake. One that has survived is the eastern fox snake.

The range of fox snakes in Canada is limited to a few pockets in southern Ontario. Although they are not considered water snakes, they are seldom found far from it. This unfortunately brings them into conflict with people with waterfront property. This loss of habitat has reduced the number of fox snakes to the point where the Ontario government has placed them on the provincial "protected species list." However, fox snakes are still quite common within Point Pelee. It has been estimated that there are more than sixty fox snakes here, but they are fairly secretive and, except when crossing the road, seldom seen.

Fox snakes can grow quite large. At Point Pelee, they occasionally reach lengths of 1.8 metres (6 feet) with a girth of 16 centimetres (6 inches). They are the Park's largest snake. As large as this may seem, the longest fox snake ever recorded was captured on the Niagara Escarpment in 1908. It measured a whopping 2.4 metres (7 feet, 11 inches).

Fox snakes are generally very docile. They readily accept gentle handling after only a short time in captivity. This is not to say that fox snakes will not defend themselves.

One defensive posture gives the snake its name. When captured, fox snakes excrete a strong substance which smells, some say, like a red fox. Like all snakes they may also strike. They are not poisonous, but they have sharp teeth and their bite can be painful.

Of all its defence mechanisms, its mimicry is one of its most interesting. When upset, a fox snake will vibrate its tail like a rattlesnake. Although it has no rattles, it sounds very convincing, especially when it's among dried leaves. Unfortunately, this has led to many of them being killed by people who are not aware of this habit.

Beach

Like the border on a quilt, Point Pelee's 20-kilometre (12-mile) beach frames the other patches of landscape: the marsh, forest and fields. It is the harshest and most dynamic of all the habitats. In summer, the temperature of the sand may reach a scorching 46°C (115°F), while in winter it is often covered in ice and snow. During storms, waves crash over it, constantly altering its shape, width and slope.

At first glance, the beach appears to be without life. In fact, it is home to a variety of hardy creatures. Even on the most storm-ridden people-trodden beaches, ants, grasshoppers, tiger beetles and spiders can survive and reproduce. Shorebirds live by patrolling the pebble ridges, seeking out this assortment of insects and spiders or any other invertebrates they might find.

The scavengers - the crows, gulls, and grackles - search the driftline for any tasty morsel: a piece of dead fish or a crunchy bug. Because of their exposed position, only the hardiest plants can survive on Point Pelee's beaches. Mostly they are grasses, but other types of plants do well here too, including one small unusual tree, the hop tree. The hop tree is the northernmost tree-sized representative of the citrus family. It seems strange that, although hop trees are found in a variety of settings as far south as Mexico, in Canada they grow exclusively along the southern fringe of southwestern Ontario, and here, in only this harsh environment.